/*
   * PCI <-> OF mapping helpers
   *
   * Copyright 2011 IBM Corp.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version
   * 2 of the License, or (at your option) any later version.
   */

  #include <linux/irqdomain.h>

  #include <linux/kernel.h>
  #include <linux/pci.h>
  #include <linux/of.h>

  #include <linux/of_irq.h>

  #include <linux/of_pci.h>
  #include "pci.h"
  
  void pci_set_of_node(struct pci_dev *dev)
  {
  	if (!dev->bus->dev.of_node)
  		return;
  	dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node,
  						    dev->devfn);
  }
  
  void pci_release_of_node(struct pci_dev *dev)
  {
  	of_node_put(dev->dev.of_node);
  	dev->dev.of_node = NULL;
  }
  
  void pci_set_bus_of_node(struct pci_bus *bus)
  {
  	if (bus->self == NULL)
  		bus->dev.of_node = pcibios_get_phb_of_node(bus);
  	else
  		bus->dev.of_node = of_node_get(bus->self->dev.of_node);
  }
  
  void pci_release_bus_of_node(struct pci_bus *bus)
  {
  	of_node_put(bus->dev.of_node);
  	bus->dev.of_node = NULL;
  }
  
  struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus)
  {
  	/* This should only be called for PHBs */
  	if (WARN_ON(bus->self || bus->parent))
  		return NULL;
  
  	/* Look for a node pointer in either the intermediary device we
  	 * create above the root bus or it's own parent. Normally only
  	 * the later is populated.
  	 */
  	if (bus->bridge->of_node)
  		return of_node_get(bus->bridge->of_node);

  	if (bus->bridge->parent && bus->bridge->parent->of_node)

  		return of_node_get(bus->bridge->parent->of_node);
  	return NULL;
  }

  
  struct irq_domain *pci_host_bridge_of_msi_domain(struct pci_bus *bus)
  {
  #ifdef CONFIG_IRQ_DOMAIN

  	struct irq_domain *d;
  
  	if (!bus->dev.of_node)
  		return NULL;
  
  	/* Start looking for a phandle to an MSI controller. */

  	d = of_msi_get_domain(&bus->dev, bus->dev.of_node, DOMAIN_BUS_PCI_MSI);
  	if (d)
  		return d;

  
  	/*
  	 * If we don't have an msi-parent property, look for a domain
  	 * directly attached to the host bridge.
  	 */

  	d = irq_find_matching_host(bus->dev.of_node, DOMAIN_BUS_PCI_MSI);

  	if (d)
  		return d;

  	return irq_find_host(bus->dev.of_node);

  #else
  	return NULL;
  #endif
  }